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Side Tube Filtering Flasks

Filtering flasks (also known as a vacuum flask, filter flask, or Buchner flask) have heavier walls than a standard Erlenmeyer flask to withstand the effects of vacuum filtration. A side arm with hose barb accepts flexible tubing for connection to vacuum pump, aspirator, or other vacuum source. During filtration, the filtrate enters and is held in the flask while the sample or residue remains on the filter paper in the funnel.